Give a proof for the standard rule of differentiation, the Chain
Rule. To do this, use the following information:
10.1.3 Suppose that the function f is differentiable at c, Then,
if f′(c) > 0 and if c is an accumulation point of the set
constructed by intersecting the domain of f with (c,∞), then there
is a δ > 0 such that at each point xin the domain of f which
lies in (c,c+δ) we have f(x) > f(c). If...